Infinity War VFX: The Josh Puppet

This small piece of nerdery from the visual effects process of Avengers: Infinity War struck me as weird, poetic and interesting:

“We used an actor puppet as part of our process of solving the facial performance,” said [Weta Digital Visual Effects Supervisor] Matt Aitken. “We had Josh Brolin’s face-cam footage, which we tracked. In the past, we would have taken that tracked motion and solved it straight onto the CG character. But, at that point, you’re always guessing how accurately you’ve captured the actor’s original performance. How much of what we’re seeing on Thanos are inaccuracies that have crept into our processes? So we introduced this intermediary stage, which was a digital version of Josh Brolin. We would first solve our captured performance onto that, so we could see how accurate it was. Once we were happy with that, we did a simple migration of that motion from the Josh puppet to the Thanos puppet. (…).”